Why did my snails die?

I had about 16 tiny snails with 2 minnows. When my minnows died, I bought a goldfish. From that afternoon, when I bought the goldfish, I found every single snail dead. Why did this happen? My snails also laid eggs.
goldfish tend to pick anything up with their mouth and think its food but when it figure out thats it is not food it spit it out and disappear it alone once it see it again it picks it up again and thats maybe the snail die
Goldfish will often guzzle snails. Also high nitrates, nitrites, or ammonia cold have kkilled your snails (and possibly your minnows). How big is your tank, likelihood are it may be too small for 2 goldfish (a 20g min is needed for hte first few years, and evenually will require bigger).
Best of luck!
Answers:    goldfish and snails are NOT compatible!!
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